Mechanically Fastened Rigid Insulation

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 Mechanically Fastened Rigid Insulation is a method of securement where the rigid insulation is attached to the deck using plates and fasteners. It is the most common form of insulation attachment used today due to its installation speed and high performance.

In a mechanically fastened insulation system, the rigid insulation is laid directly over the substrate. Once the rigid insulation is in place, plates and fasteners are installed in every piece of insulation. The amount of plates and fasteners used per 4’ by 8’ rigid insulation board varies based on the system type.

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  • If the membrane is mechanically attached, there are typically around 6-8 fasteners per 4’ by 8’ rigid insulation sheet.
  • For a fully adhered membrane installation, the number of fasteners ranges from 12 to 24 depending on the manufacturer, warranty length, and a variety of other factors.
  • With ballasted roof systems, no fasteners are used.
  • On Rhinobond systems the number varies based on where the insulation is located, and installed with a special rigid insulation plate.

Mechanically attached rigid insulation systems are ideal for most locations. The installation is quick and the product is secure for years. If there is an area where fasteners are not the best way to install the roof system, such as over a concrete deck where pre-drilling is disruptive, adhesives might be a better option. Check out Olybond Rigid Insulation Attachment, paired with a fully adhered roof.